کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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294511 | 511485 | 2011 | 5 صفحه PDF | دانلود رایگان |
X-ray diffraction (XRD) was used to study the structure of the organic crystallite unit (La, Lc, d002) in coals collected from Henan and Shanxi Provinces. XRD patterns of coal were collected in a step-scan mode (0.1°/step) over an angular range of 2–90° (2θ), allowing 8 s at each step. The structure of the crystallite unit was determined from the Scherrer equation and peak parameters deduced from whole pattern fitting. The results show that the structure of the crystallite unit in coal is mainly controlled by the coal rank. As the coal rank increases the average diameter of a coal crystallite unit (La) increases, the inter-layer spacing (d002) decreases slightly, and the average height of a coal crystallite unit (Lc) increases at first but then decreases. A new diffraction peak from the crystallite unit in coal was found at a low scattering angle in the XRD pattern (2–10°). This suggests a structure with an inter-layer spacing from 1.9 to 2.8 nm exists in coal crystallites.
Journal: Mining Science and Technology (China) - Volume 21, Issue 5, September 2011, Pages 667–671